The most hottest and humid air mass of the summer so far occupied Eastern Pennsylvania from the 25th through the 27th. This air mass had as its origin the desert southwest in the United States and a ridge of high pressure aloft brought this air mass east with it through the rest of the country. The hottest and most humid day was the 27th. This was the hottest day of the year so far for most places and the highest temperatures seen in many areas since August of 2002. The combination of high temperatures and humidity levels pushed afternoon heat indices to between 105 and 110 degrees around the Greater Philadelphia Metropolitan Area on the 27th. Five elderly persons succumbed to the heat within Philadelphia and two elderly persons died because of the heat in Montgomery County. Most were found in homes with no working air conditioners or air conditioners at all. But, an 88-year-old woman in Pottstown (Montgomery County) was found dead slumped over the steering wheel of her vehicle in a shopping center. The car doors and windows were closed. Hospitals saw an increase in the number of patients complaining about dizziness, allergies and breathing difficulties. Schools in Philadelphia whether they had air conditioning or not dismissed the children early. Delaware Park cancelled their horse racing card on the 27th. Outdoor activities for prisoners in Philadelphia were cancelled. The PJM Interconnection recorded a world record for electricity usage on the 26th: 135,000 megawatts. The PJM coordinates the movement of electricity in Pennsylvania and twelve other states from North Carolina to Illinois. On the 27th, PJM lowered voltage to certain customers by five percent due to the stress on the high voltage lines. Locally PECO Energy (in and around Philadelphia) established back-to-back record usage days of 8,209 megawatts in an hour on the 26th and 8,329 megawatt in an hour on the 27th. Both surpassed the previous record of 8,164 megawatts set in August of 2002. The utility also established an all-time daily record usage of 165.7 million kilowatts surpassing the previous record of 163 million kilowatts set in July of 1999.  Other utilities also set new usage records including Metropolitan Edison (2,792 megawatts in an hour) and Pennsylvania Power and Light (7,035 megawatts in an hour). The excessive heat activated special summer heat programs in Philadelphia. Homes of the elderly were visited by field teams, "The Heatline" was activated by the Philadelphia Corporation for the Elderly, there was an enhanced daytime outreach for the homeless and the buddy system to check on the elderly was activated. Chester County distributed all the available fans they had to the elderly. Delaware County encouraged the elderly to visit their senior citizen centers. In the Lehigh Valley, free rides were given on air-conditioned buses by the Lehigh and Northampton Transportation Authority. A code red was declared by Montgomery County. People were not the only ones suffering as repair shops were swamped with air-conditioning repairs for vehicles. Farmers were also noting that livestock was also affected by the heat as they were not eating much and were not gaining weight and/or producing less milk.A cold front abruptly ended the hot weather as it moved through the eastern part of the state late in the afternoon and early in the evening on the 27th.  The highest temperatures included 98 degrees at the Philadelphia International Airport and West Chester (Chester County), 96 degrees in Doylestown (Bucks County), 95 degrees in Reading (Berks County), 94 degrees at the Lehigh Valley International Airport and Pottstown (Montgomery County) and 93 degrees in Forks Township (Northampton County).

Heat in BERKS, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in BUCKS, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in CHESTER, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in DELAWARE, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in LEHIGH, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in MONTGOMERY, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in NORTHAMPTON, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC

Heat in PHILADELPHIA, PENNSYLVANIA
From 25-JUL-05 09:00:00 to 27-JUL-05 17:00:00 (EST)
Reported by: AWOS,ASOS,MESONET,ETC